Carbon nanotubes (CNTs) are carbon allotropes having a generally cylindrical nanostructure. They have unusual properties that make them valuable for many different technologies. For instance, some CNTs can have high thermal and electrical conductivity, making them suitable for replacing metal heating elements. Due to their much lighter mass, substituting CNTs for metal heating components can reduce the overall weight of a heating component significantly. This makes the use of CNTs of particular interest for applications where weight is critical, such as in aerospace and aviation technologies.
Carbon nanotubes are commercially available in several different forms. One such form is a thermoplastic film filled with CNTs. In a CNT-filled thermoplastic film, individual CNTs are distributed throughout the film. However, the electrical resistivity of these commercially available, CNT-filled thermoplastic films is generally in the range of 3×10−4 ohms-cm (Ω-cm) or higher. This level of electrical resistivity is not suitable for many aerospace heating applications (e.g., anti-icing and de-icing). Thus, commercially available CNT-filled thermoplastic films cannot currently be used as a substitute for metal heating elements.